<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      const arr = [1, 2, 3];
      const str = "abc";
      const s = new Set();
      s.add("css").add("html");
      const m = new Map();
      m.set("name", "jack").set("age", 20);
      console.log([...arr]);
      console.log([...str]);
      console.log([...s]);
      console.log([...m]);
    </script>
  </body>
</html>
